iOS MapKit Annotation，未显示正确的位置 [英] iOS MapKit Annotation, not showing correct location

问题描述

我使用自定义图像进行mapkit注释。但是我在使用自定义图像时遇到的主要问题是，当缩小时，注释不在地图上的正确位置，并且只有在我一直向下放大时，它才会显示注释点在正确的位置。似乎当我使用常规引脚 MKPinAnnotationView 时，它正常工作，因为引脚位于正确的位置放大或缩小，提前感谢任何可以提供帮助的人。

I using a custom image for my mapkit annotation. But the main problem it seems that I am running into in using a custom image, is that when zoomed out, the annotation is not in the correct point on the map, and ONLY until I zoom in all the way down, will it show the annotation point in the correct place. It seems that when I use a regular pin MKPinAnnotationView, it works normally, as with the pin being in the correct place zoomed in or out, thanks in advance for anyone that can help.

我使用的代码如下：

- (MKAnnotationView *)mapView:(MKMapView *)aMapView viewForAnnotation:(id <MKAnnotation>)annotation
{

NSLog(@"welcome into the map view annotation");

if ([annotation isKindOfClass:[MKUserLocation class]])

return nil;

MKAnnotationView *pprMapNote = [[MKAnnotationView alloc] initWithAnnotation:annotation reuseIdentifier:@"pprMapNote"];


pprMapNote.image = [UIImage imageNamed:[NSString stringWithFormat:@"GPS_note.png"]];

pprMapNote.canShowCallout = YES;
pprMapNote.centerOffset = CGPointMake(-21,-60);
pprMapNote.calloutOffset = CGPointMake(0, 0);
//[pprMapNote addSubview:pprMapNoteImg];

UIButton* rightButton = [UIButton buttonWithType:UIButtonTypeDetailDisclosure];
[rightButton addTarget:self
                action:@selector(showDetail)
      forControlEvents:UIControlEventTouchUpInside];
pprMapNote.rightCalloutAccessoryView = rightButton;

//remember to write in conditional for the different icons that should be loaded based on location

UIImageView *pprNoteLocIcon = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"loc_icon_casino.png"]];
pprMapNote.leftCalloutAccessoryView = pprNoteLocIcon;
[pprNoteLocIcon release];

return pprMapNote;

}

推荐答案

你是设置注释视图的 centerOffset 。

You are setting the centerOffset of the annotation view.

请注意，此偏移量不与缩放级别缩放。缩小越远，图像将从坐标开始越远。

Note that this offset is not scaled with the zoom level. The further you zoom out, the further the image will appear from the coordinate.

在默认 MKPinAnnotationView 中， centerOffset 保留默认值0,0并且引脚图像的设计使得引脚的底点位于坐标上。因此，当你进一步缩小时，引脚图像似乎相对于它下面的地图增长，但引脚的底部仍然指向坐标。

In the default MKPinAnnotationView, the centerOffset is left at the default of 0,0 and the pin image is designed such that the bottom point of the pin is on the coordinate. So as you zoom further out, the pin image seems to grow relative to the map under it but the bottom of the pin is still pointing to the coordinate.

你需要根据您的图像调整 centerOffset 或修改您的图像，这样您就不需要设置 centerOffset 。或者只是尝试评论 centerOffset 的设置 - 也许你不需要它。

You need to either adjust the centerOffset based on your image or modify your image so you don't need to set centerOffset. Or just try commenting out the setting of centerOffset--maybe you don't need it.

一些其他不相关的项目：

Some other unrelated items:

• pprMapNote alloc + init（添加自动释放）


• 您应该使用 dequeueReusableAnnotationViewWithIdentifier 来允许重复使用注释视图。


• 使用地图视图自己的委托方法<$>而不是使用 addTarget 来调用你自己的方法按下标注按钮<$> c $ c> calloutAccessoryControlTapped

• You have a memory leak for the pprMapNote alloc+init (add an autorelease)
• You should be using dequeueReusableAnnotationViewWithIdentifier to allow for annotation view re-use.
• Instead of using addTarget to call your own method for the callout button press, it's much better to use the map view's own delegate method calloutAccessoryControlTapped

参见这个答案以上三点的例子。

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